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<div class="header">
  <div class="summary">
<a href="#func-members">Functions</a>  </div>
  <div class="headertitle">
<div class="title">Query I/O API backends registry<div class="ingroups"><a class="el" href="../../dd/de7/group__videoio.html">Video I/O</a></div></div>  </div>
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<div class="contents">
<table class="memberdecls">
<tr class="heading"><td colspan="2"><h2 class="groupheader"><a name="func-members"></a>
Functions</h2></td></tr>
<tr class="memitem:ga6723e68832186e20bd44cd3c2b0d8c60"><td align="right" class="memItemLeft" valign="top"><a class="el" href="../../dc/d84/group__core__basic.html#ga1f6634802eeadfd7245bc75cf3e216c2">cv::String</a> </td><td class="memItemRight" valign="bottom"><a class="el" href="../../de/db1/group__videoio__registry.html#ga6723e68832186e20bd44cd3c2b0d8c60">cv::videoio_registry::getBackendName</a> (<a class="el" href="../../d4/d15/group__videoio__flags__base.html#ga023786be1ee68a9105bf2e48c700294d">VideoCaptureAPIs</a> api)</td></tr>
<tr class="memdesc:ga6723e68832186e20bd44cd3c2b0d8c60"><td class="mdescLeft"> </td><td class="mdescRight">Returns backend API name or "UnknownVideoAPI(xxx)".  <a href="../../de/db1/group__videoio__registry.html#ga6723e68832186e20bd44cd3c2b0d8c60">More...</a><br/></td></tr>
<tr class="separator:ga6723e68832186e20bd44cd3c2b0d8c60"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:ga6a5310ef846956a4c38dcd293bbab5d3"><td align="right" class="memItemLeft" valign="top">std::vector&lt; <a class="el" href="../../d4/d15/group__videoio__flags__base.html#ga023786be1ee68a9105bf2e48c700294d">VideoCaptureAPIs</a> &gt; </td><td class="memItemRight" valign="bottom"><a class="el" href="../../de/db1/group__videoio__registry.html#ga6a5310ef846956a4c38dcd293bbab5d3">cv::videoio_registry::getBackends</a> ()</td></tr>
<tr class="memdesc:ga6a5310ef846956a4c38dcd293bbab5d3"><td class="mdescLeft"> </td><td class="mdescRight">Returns list of all available backends.  <a href="../../de/db1/group__videoio__registry.html#ga6a5310ef846956a4c38dcd293bbab5d3">More...</a><br/></td></tr>
<tr class="separator:ga6a5310ef846956a4c38dcd293bbab5d3"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:gaf6e7163ade0d35b946c3ccccaf504e3e"><td align="right" class="memItemLeft" valign="top">std::vector&lt; <a class="el" href="../../d4/d15/group__videoio__flags__base.html#ga023786be1ee68a9105bf2e48c700294d">VideoCaptureAPIs</a> &gt; </td><td class="memItemRight" valign="bottom"><a class="el" href="../../de/db1/group__videoio__registry.html#gaf6e7163ade0d35b946c3ccccaf504e3e">cv::videoio_registry::getCameraBackends</a> ()</td></tr>
<tr class="memdesc:gaf6e7163ade0d35b946c3ccccaf504e3e"><td class="mdescLeft"> </td><td class="mdescRight">Returns list of available backends which works via <code><a class="el" href="../../d8/dfe/classcv_1_1VideoCapture.html" title="Class for video capturing from video files, image sequences or cameras. ">cv::VideoCapture(int index)</a></code>  <a href="../../de/db1/group__videoio__registry.html#gaf6e7163ade0d35b946c3ccccaf504e3e">More...</a><br/></td></tr>
<tr class="separator:gaf6e7163ade0d35b946c3ccccaf504e3e"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:ga40e7ee1ae84a92bcc949dfab9d34b7c5"><td align="right" class="memItemLeft" valign="top">std::vector&lt; <a class="el" href="../../d4/d15/group__videoio__flags__base.html#ga023786be1ee68a9105bf2e48c700294d">VideoCaptureAPIs</a> &gt; </td><td class="memItemRight" valign="bottom"><a class="el" href="../../de/db1/group__videoio__registry.html#ga40e7ee1ae84a92bcc949dfab9d34b7c5">cv::videoio_registry::getStreamBackends</a> ()</td></tr>
<tr class="memdesc:ga40e7ee1ae84a92bcc949dfab9d34b7c5"><td class="mdescLeft"> </td><td class="mdescRight">Returns list of available backends which works via <code><a class="el" href="../../d8/dfe/classcv_1_1VideoCapture.html" title="Class for video capturing from video files, image sequences or cameras. ">cv::VideoCapture(filename)</a></code>  <a href="../../de/db1/group__videoio__registry.html#ga40e7ee1ae84a92bcc949dfab9d34b7c5">More...</a><br/></td></tr>
<tr class="separator:ga40e7ee1ae84a92bcc949dfab9d34b7c5"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:gab094008034f9b4d7006e8a892b8c65ff"><td align="right" class="memItemLeft" valign="top">std::vector&lt; <a class="el" href="../../d4/d15/group__videoio__flags__base.html#ga023786be1ee68a9105bf2e48c700294d">VideoCaptureAPIs</a> &gt; </td><td class="memItemRight" valign="bottom"><a class="el" href="../../de/db1/group__videoio__registry.html#gab094008034f9b4d7006e8a892b8c65ff">cv::videoio_registry::getWriterBackends</a> ()</td></tr>
<tr class="memdesc:gab094008034f9b4d7006e8a892b8c65ff"><td class="mdescLeft"> </td><td class="mdescRight">Returns list of available backends which works via <code><a class="el" href="../../dd/d9e/classcv_1_1VideoWriter.html" title="Video writer class. ">cv::VideoWriter()</a></code>  <a href="../../de/db1/group__videoio__registry.html#gab094008034f9b4d7006e8a892b8c65ff">More...</a><br/></td></tr>
<tr class="separator:gab094008034f9b4d7006e8a892b8c65ff"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:ga9068310d50ef430c2f5f6b185a99a24b"><td align="right" class="memItemLeft" valign="top">bool </td><td class="memItemRight" valign="bottom"><a class="el" href="../../de/db1/group__videoio__registry.html#ga9068310d50ef430c2f5f6b185a99a24b">cv::videoio_registry::hasBackend</a> (<a class="el" href="../../d4/d15/group__videoio__flags__base.html#ga023786be1ee68a9105bf2e48c700294d">VideoCaptureAPIs</a> api)</td></tr>
<tr class="memdesc:ga9068310d50ef430c2f5f6b185a99a24b"><td class="mdescLeft"> </td><td class="mdescRight">Returns true if backend is available.  <a href="../../de/db1/group__videoio__registry.html#ga9068310d50ef430c2f5f6b185a99a24b">More...</a><br/></td></tr>
<tr class="separator:ga9068310d50ef430c2f5f6b185a99a24b"><td class="memSeparator" colspan="2"> </td></tr>
</table>
<a id="details" name="details"></a><h2 class="groupheader">Detailed Description</h2>
<p>This section contains API description how to query/configure available Video I/O backends.</p>
<p>Runtime configuration options:</p><ul>
<li>enable debug mode: <code>OPENCV_VIDEOIO_DEBUG=1</code></li>
<li>change backend priority: <code>OPENCV_VIDEOIO_PRIORITY_&lt;backend&gt;=9999</code></li>
<li>disable backend: <code>OPENCV_VIDEOIO_PRIORITY_&lt;backend&gt;=0</code></li>
<li>specify list of backends with high priority (&gt;100000): <code>OPENCV_VIDEOIO_PRIORITY_LIST=FFMPEG,GSTREAMER</code> </li>
</ul>
<h2 class="groupheader">Function Documentation</h2>
<a id="ga6723e68832186e20bd44cd3c2b0d8c60"></a>
<h2 class="memtitle"><span class="permalink"><a href="#ga6723e68832186e20bd44cd3c2b0d8c60">◆ </a></span>getBackendName()</h2>
<div class="memitem">
<div class="memproto">
      <table class="memname">
        <tr>
          <td class="memname"><a class="el" href="../../dc/d84/group__core__basic.html#ga1f6634802eeadfd7245bc75cf3e216c2">cv::String</a> cv::videoio_registry::getBackendName </td>
          <td>(</td>
          <td class="paramtype"><a class="el" href="../../d4/d15/group__videoio__flags__base.html#ga023786be1ee68a9105bf2e48c700294d">VideoCaptureAPIs</a> </td>
          <td class="paramname"><em>api</em></td><td>)</td>
          <td></td>
        </tr>
      </table><table class="python_language"><tr><th colspan="999" style="text-align:left">Python:</th></tr><tr><td style="width: 20px;"></td><td>retval</td><td>=</td><td>cv.videoio_registry.getBackendName(</td><td class="paramname">api</td><td>)</td></tr></table>
</div><div class="memdoc">
<p><code>#include &lt;<a class="el" href="../../d1/da2/registry_8hpp.html">opencv2/videoio/registry.hpp</a>&gt;</code></p>
<p>Returns backend API name or "UnknownVideoAPI(xxx)". </p>
<dl class="params"><dt>Parameters</dt><dd>
  <table class="params">
    <tr><td class="paramname">api</td><td>backend ID (<a class="el" href="../../d4/d15/group__videoio__flags__base.html#ga023786be1ee68a9105bf2e48c700294d" title="cv::VideoCapture API backends identifier. ">VideoCaptureAPIs</a>) </td></tr>
  </table>
  </dd>
</dl>
</div>
</div>
<a id="ga6a5310ef846956a4c38dcd293bbab5d3"></a>
<h2 class="memtitle"><span class="permalink"><a href="#ga6a5310ef846956a4c38dcd293bbab5d3">◆ </a></span>getBackends()</h2>
<div class="memitem">
<div class="memproto">
      <table class="memname">
        <tr>
          <td class="memname">std::vector&lt;<a class="el" href="../../d4/d15/group__videoio__flags__base.html#ga023786be1ee68a9105bf2e48c700294d">VideoCaptureAPIs</a>&gt; cv::videoio_registry::getBackends </td>
          <td>(</td>
          <td class="paramname"></td><td>)</td>
          <td></td>
        </tr>
      </table><table class="python_language"><tr><th colspan="999" style="text-align:left">Python:</th></tr><tr><td style="width: 20px;"></td><td>retval</td><td>=</td><td>cv.videoio_registry.getBackends(</td><td class="paramname"></td><td>)</td></tr></table>
</div><div class="memdoc">
<p><code>#include &lt;<a class="el" href="../../d1/da2/registry_8hpp.html">opencv2/videoio/registry.hpp</a>&gt;</code></p>
<p>Returns list of all available backends. </p>
</div>
</div>
<a id="gaf6e7163ade0d35b946c3ccccaf504e3e"></a>
<h2 class="memtitle"><span class="permalink"><a href="#gaf6e7163ade0d35b946c3ccccaf504e3e">◆ </a></span>getCameraBackends()</h2>
<div class="memitem">
<div class="memproto">
      <table class="memname">
        <tr>
          <td class="memname">std::vector&lt;<a class="el" href="../../d4/d15/group__videoio__flags__base.html#ga023786be1ee68a9105bf2e48c700294d">VideoCaptureAPIs</a>&gt; cv::videoio_registry::getCameraBackends </td>
          <td>(</td>
          <td class="paramname"></td><td>)</td>
          <td></td>
        </tr>
      </table><table class="python_language"><tr><th colspan="999" style="text-align:left">Python:</th></tr><tr><td style="width: 20px;"></td><td>retval</td><td>=</td><td>cv.videoio_registry.getCameraBackends(</td><td class="paramname"></td><td>)</td></tr></table>
</div><div class="memdoc">
<p><code>#include &lt;<a class="el" href="../../d1/da2/registry_8hpp.html">opencv2/videoio/registry.hpp</a>&gt;</code></p>
<p>Returns list of available backends which works via <code><a class="el" href="../../d8/dfe/classcv_1_1VideoCapture.html" title="Class for video capturing from video files, image sequences or cameras. ">cv::VideoCapture(int index)</a></code> </p>
</div>
</div>
<a id="ga40e7ee1ae84a92bcc949dfab9d34b7c5"></a>
<h2 class="memtitle"><span class="permalink"><a href="#ga40e7ee1ae84a92bcc949dfab9d34b7c5">◆ </a></span>getStreamBackends()</h2>
<div class="memitem">
<div class="memproto">
      <table class="memname">
        <tr>
          <td class="memname">std::vector&lt;<a class="el" href="../../d4/d15/group__videoio__flags__base.html#ga023786be1ee68a9105bf2e48c700294d">VideoCaptureAPIs</a>&gt; cv::videoio_registry::getStreamBackends </td>
          <td>(</td>
          <td class="paramname"></td><td>)</td>
          <td></td>
        </tr>
      </table><table class="python_language"><tr><th colspan="999" style="text-align:left">Python:</th></tr><tr><td style="width: 20px;"></td><td>retval</td><td>=</td><td>cv.videoio_registry.getStreamBackends(</td><td class="paramname"></td><td>)</td></tr></table>
</div><div class="memdoc">
<p><code>#include &lt;<a class="el" href="../../d1/da2/registry_8hpp.html">opencv2/videoio/registry.hpp</a>&gt;</code></p>
<p>Returns list of available backends which works via <code><a class="el" href="../../d8/dfe/classcv_1_1VideoCapture.html" title="Class for video capturing from video files, image sequences or cameras. ">cv::VideoCapture(filename)</a></code> </p>
</div>
</div>
<a id="gab094008034f9b4d7006e8a892b8c65ff"></a>
<h2 class="memtitle"><span class="permalink"><a href="#gab094008034f9b4d7006e8a892b8c65ff">◆ </a></span>getWriterBackends()</h2>
<div class="memitem">
<div class="memproto">
      <table class="memname">
        <tr>
          <td class="memname">std::vector&lt;<a class="el" href="../../d4/d15/group__videoio__flags__base.html#ga023786be1ee68a9105bf2e48c700294d">VideoCaptureAPIs</a>&gt; cv::videoio_registry::getWriterBackends </td>
          <td>(</td>
          <td class="paramname"></td><td>)</td>
          <td></td>
        </tr>
      </table><table class="python_language"><tr><th colspan="999" style="text-align:left">Python:</th></tr><tr><td style="width: 20px;"></td><td>retval</td><td>=</td><td>cv.videoio_registry.getWriterBackends(</td><td class="paramname"></td><td>)</td></tr></table>
</div><div class="memdoc">
<p><code>#include &lt;<a class="el" href="../../d1/da2/registry_8hpp.html">opencv2/videoio/registry.hpp</a>&gt;</code></p>
<p>Returns list of available backends which works via <code><a class="el" href="../../dd/d9e/classcv_1_1VideoWriter.html" title="Video writer class. ">cv::VideoWriter()</a></code> </p>
</div>
</div>
<a id="ga9068310d50ef430c2f5f6b185a99a24b"></a>
<h2 class="memtitle"><span class="permalink"><a href="#ga9068310d50ef430c2f5f6b185a99a24b">◆ </a></span>hasBackend()</h2>
<div class="memitem">
<div class="memproto">
      <table class="memname">
        <tr>
          <td class="memname">bool cv::videoio_registry::hasBackend </td>
          <td>(</td>
          <td class="paramtype"><a class="el" href="../../d4/d15/group__videoio__flags__base.html#ga023786be1ee68a9105bf2e48c700294d">VideoCaptureAPIs</a> </td>
          <td class="paramname"><em>api</em></td><td>)</td>
          <td></td>
        </tr>
      </table>
</div><div class="memdoc">
<p><code>#include &lt;<a class="el" href="../../d1/da2/registry_8hpp.html">opencv2/videoio/registry.hpp</a>&gt;</code></p>
<p>Returns true if backend is available. </p>
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